Based on the special research capabilities and resources at Yerkes, national health research needs, and the need for a balanced total Center's program, the following general missions have been identified for this Center: (1) Neural and behavioral research and (2) Experimental pathology with emphasis on neoplastic and degenerative diseases. The Yerkes Center has a worldwide reputation in the area of behavior using the great apes as the experimental animal. Selected studies in this area, and in Immunology and Great Ape Reproduction, will continue as long as they remain productive. However, the Center's efforts have been expanded to emphasize the modern techniques of neurophysiology and neurochemistry in studies which will contribute directly to the understanding of the neurological processes involved in behavior and will have a more direct fundamental application to human health and neurological problems. These techniques involve the electrical stimulation of different parts of the brain, studies of brain chemistry, the relationship between hormones and behavior, studies in psychopharmacology, and neuroanatomy research. The second major emphasis involves experimental pathology, especially neoplastic and degenerative diseases, and experimental nutrition for the purpose of determining the effects of diet on behavior. Current and projected programs in support of these objectives are submitted with this application.